


The Undertow

by topazastral



Category: The Magnus Archives (Podcast)
Genre: M/M, drowning tw, mermaid au, mostly fluff with a bit of angst towards the end, paddleboarder au
Language: English
Status: In-Progress
Published: 2021-03-08
Updated: 2021-03-11
Packaged: 2021-03-14 07:14:46
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 3
Words: 3,552
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29913327
Author URL: https://archiveofourown.org/users/topazastral/pseuds/topazastral
Summary: A summer on the river is just what Martin Blackwood needs to get away. Of course, that isn't accounting for what might be hidden under the waves.
Relationships: Jonathan Sims/Martin Blackwood, Martin Blackwood & Sasha James, Martin Blackwood & Tim Stoker
Comments: 17
Kudos: 44





	1. In Which Martin Blackwood Tries His Best Not to Drown

**Author's Note:**

> This is the first fic I've gotten the courage to post to AO3! Quick disclaimer: I am Jewish, so I don't write out the word "G-d." However, Martin (at least in this fic) is not Jewish. I feel as if making him Jewish would play into the nagging Jewish mother stereotype, so I wanted to clarify.  
> This is also inspired by the lovely art of @vanecksweater on tumblr!

Martin Blackwood loves the river. He loves its bends and curves, its drops and its holes, the way the roar of the whitewater and the adrenaline it sends pounding through his body drown out the thoughts in his head.

He would love the river more if it wouldn’t send him swimming every time he tried surfing this wave. A kayaker is laughing at him and he knows it’d be _such_ a good surf if his board would stop dipping.

After he emerges for the seventh time, soaked from the roughly tumbling water, he decides that this is his last try before he continues downstream. He’ll have to carry his board down the bank, of course. The next rapid looks _very_ fun, but those rocks look...less so.

Deep breath in. Hold. Line up the paddleboard with the trough of the wave. Not too straight, or the nose will catch and get dragged underwater. Not too sideways, or he’ll flip. Lean with the flow of the current. Dig your paddle in on the downstream side. Deep breath out.

Martin strokes into the rapid, knees braced against the foam deck of his board, body clenched against the onslaught of the swift water. He dips into the wave, paddleboard pitching forward, but just manages to stay on. For a second, he’s caught up in the crest of the wave, and he relishes the feeling of stability, before the river decides that actually, it doesn’t like him, and his board flips. Wonderful.

As the water breaks and crashes over his head, he lets himself just float there for a moment, carried along by the wave train. Feels almost peaceful, though a bit jostly. He wonders briefly what sort of wildlife live in and around this river. He’s new to it, obviously; the rivers that he’s used to are nothing like this. Much smaller, with less intense rapids. Wait, no, now he’s thinking of the Bolton Strid. Eurgh. That awful thing makes the pit of his stomach go all weird. 

“Get out of there, man!” A voice startles him out of his contemplation. This current is way faster than he realized. He is much, _much_ too close to the bottom of this rapid, which turns into a g-ddamn chute. _Like a waterfall_ , he thinks, _if waterfalls had a particular hatred of G-d and also the laws of physics._

Not the time, Martin.

He scrambles back onto his board, most definitely _not_ panicking. Martin is now paddling as fast as he physically can towards the eddy. He’s always been a strong paddler, but he knows that it isn’t going to be enough. Well. Time to hope he comes out the other side of this. 

There’s always a single moment, before he hits a rapid, whether he’s on his board or not, where he remembers that oh, what he’s doing is kind of insane, actually. 

Certainly is fun, though. He braces himself for the first drop, and as the front of his board charges through the water and meets nothing but air, he feels his stomach drop. He’s going to go for a nice little swim, he reckons.

Dimly, he registers the kayaker in his peripheral vision, probably trying to get him a throw rope or something. He’ll be fine. Probably. It’s sketchy, but he’s done worse before.

Martin is plunged under the water, current tugging him downwards as he feels bubbles rising around him, tickling his skin. He feels his body being dragged away from the surface, and he instinctively curls into a ball, forgetting all proper rapid-swimming technique. It never sticks long when you’re in this kind of thing.

He emerges in the dead center of the rapid, sweeping him along like a leaf caught in a windstorm. For a single moment, he stares up at a looming wave, dread settling into his heart, and as he gulps a deep breath, he knows this one is going to _suck_.

He is once more dunked under, lungs immediately contracting and expelling precious air. He flails blindly, arms and legs hitting--something? Something--well, not _soft_ , exactly, but not a rock or a log. Slightly pliable, but tough. His spine hits something bony, and all of a sudden he feels a gripping pressure encircling his neck. Any meaningful amount of breath he once had is now completely gone, lost to the depths of the foaming river.

Martin’s vision begins to blacken, and he starts to choke. He can feel the tug of his life jacket, though, gently ushering him towards the surface as whatever is gripping his neck forces him downwards.

 _Not today_ , Martin thinks, and twists, violently, hoping to break free of whatever’s restraining him. He can feel his lungs burn and ache, longing for oxygen that they don’t have. He swings his legs underneath him, following the pull of the life jacket, hoping that he’ll somehow be able to reach the open air in time.

Martin expects to feel the thin tendrils of a river plant, or the rough fibers of a discarded rope. What Martin does not expect is for his thrashing leg to brush up against something _really weird_. It feels _scaly_ , like some sort of giant fish. Like...some sort of _giant fish_.

Martin files this information away for later when he is not drowning, instead choosing to focus on the slightly more pressing issue. He writhes, unable to shake not only the feeling that this thing is trying to grapple him, but also the grapple itself. He can sense his consciousness fade and as he attempts to swim up one last time, he feels his elbow hit something. He could have sworn he heard something crunch, and he hopes he did some damage. _Too late_ , he thinks, drifting towards the rays of sun hitting the murky water. The waves are gone; whatever it was must have dragged him into an eddy. Small blessings.

Martin’s eyelids shudder shut, and with his second-to-last conscious thought, he prays for his limp body to reach air. His last thought is a vague notion of irritation towards the damn river.


	2. In Which Martin Blackwood Finds a Friend

Martin comes back to consciousness to find himself staring into the wide eyes of a very, very handsome man.

“Shit, are you OK?” asks the man, whose face is starting to look oddly familiar. Martin now realizes that he’s lying on his side, arm crooked beneath his head, body resting on pebbled ground. It’s oddly comfortable; not what he would expect for a person that had just escaped a near-death by drowning.

The man notices Martin’s frown. “Recovery position,” he explains. “You had a lot of water in your lungs.”

“I, ah...thank you?” Martin says. He pushes himself upright, awkwardly bringing his legs in towards his body.

“You’re welcome!” The man grins, leaning back. “S-Turn’s a nasty one, isn’t it?”

“Oh, uh--is that what that rapid is called? I’m a--I’m a little new here.”

“I can tell!” The man chuckles. “No offense intended, of course--you seem like a lovely guy. But I haven’t met a lot of people who would swim down that.”

Martin rubs the back of his neck, grimacing. Both in embarrassment, and because of the water in his respiratory system, which is now trying to expel itself as violently as possible. “Dunno if you’d call what I did ‘swimming’.”

He laughs again, long and low. Martin hopes he isn’t blushing too much. “The name’s Tim, by the way. Tim Stoker.” He gestures behind him, waving a hand. “Believe we’ve met before? Briefly. But still.”

“Ohhh,” Martin says, noticing the orange kayak behind him. A playboat, if he isn’t mistaken. “You were, uh, the one up by that wave?”

“Sure was! That’s a hard one to surf, by the way. Impressed you managed it.”

Martin rolls his eyes. “Barely.” He looks down at himself. He’s got a few cuts and bruises, especially on his legs, and he knows that his muscles are going to _ache_ tomorrow. His throat is sore as well, and he winces as he tries to take a deep breath.

Tim nods in sympathy. “Had a few nasty swims myself, before. Seems like you had a rougher time of it, though.”

“You don’t say,” says Martin, voice dry. Unlike his lungs, which are currently trying to burn a hole in his chest. “Actually, though--you’re from around here, right? Er, do you know of any sort--any sort of large creature that lives in the water near here?”

Tim gives him a blank stare. “Nothing that I can think of. Why?” He brightens. “Are you interested in that kind of thing? My friend--Sasha--she really likes that stuff.”

Martin coughs, a bit of river water coming up. Not a pleasant taste. “Ah--no. Just wondering.” He frowns, realizing. “You didn’t--you wouldn’t have happened to find my gear, would you?”

“Afraid not,” Tim says, shaking his head ruefully. “Sorry ‘bout that. I could ask around, if you like? Sometimes stuff will wash out and people’ll bring it up back here.”

“That’d be nice.” Martin smiles. He hopes it looks like a smile, at least.

“Yeah, the community here is really great,” Tim adds, sitting down in one easy, fluid motion. “Everyone’s just super nice. Hey, speaking of which, you should hang out with me and Sash sometime!”

 _Today has been an interesting day,_ Martin thinks. _Why not?_

“Sure!” he says, shrugging. “I mean, ah...you did save me from drowning, so…”

Tim grins. “Glad to hear it, man.”

Martin’s mother is most certainly _not pleased_ with his near-death experience on the river. He spends an uncomfortable half hour with her on the phone, mostly tuning her voice out to focus on the river. Could almost be relaxing, what with the gently swaying plants and assorted darting winged things. It is not, however, relaxing, with her grating words rattling around his brain. She’s...not wrong, exactly; the things he’s doing could lead to severe harm or injury, but he’s an adult. He can make his own decisions, for goodness’s sake. 

Martin thinks she might be able to _hear_ him rolling his eyes. G-d.

When she finally lets up, extricating a promise to call her back tonight, please, so she doesn’t have to worry that he’s hit his head on a rock and drowned, Martin sighs, breath leaving his body in a slow exhale, chest collapsing. _Urgh_.

Well, at least there’s Tim and the still-faceless Sasha. Tim had asked him if he was free tomorrow, and Martin had responded with a noncommittal noise. Which had been the truth, of course; honestly, he hadn’t known if his mother would let him stay. He counted himself lucky that she had. 

Martin wasn’t quite ready to end this strange trip yet, given what he’d...felt...in the river. There was _no way_ in hell that thing was normal. And he would have been willing to chalk it up to lack of oxygen, were it not for the single scale caught in his swimsuit, muddy brown and dagger-sharp. Or, at least...muddy brown, until the late-afternoon sun hit it just so, setting it afire in marbled tones of iridescent green and sparkling beige.

Martin’s pretty sure _that_ isn’t normal.


	3. In Which Martin Blackwood Leaves a Message

Martin’s mother is most certainly  _ not pleased _ with his near-death experience on the river. He spends an uncomfortable half hour with her on the phone, mostly tuning her voice out to focus on the river. Could almost be relaxing, what with the gently swaying plants and assorted darting winged things. It is not, however, relaxing, with her grating words rattling around his brain. She’s...not wrong, exactly; the things he’s doing could lead to severe harm or injury, but he’s an adult. He can make his own decisions, for goodness’s sake. 

Martin thinks she might be able to  _ hear _ him rolling his eyes. G-d.

When she finally lets up, extricating a promise to call her back tonight, please, so she doesn’t have to worry that he’s hit his head on a rock and drowned, Martin sighs, breath leaving his body in a slow exhale, chest collapsing.  _ Urgh _ .

Well, at least there’s Tim and the still-faceless Sasha. Tim had asked him if he was free tomorrow, and Martin had responded with a noncommittal noise. Which had been the truth, of course; honestly, he hadn’t known if his mother would let him stay. He counted himself lucky that she had. 

Martin wasn’t quite ready to end this strange trip yet, given what he’d...felt...in the river. There was  _ no way _ in hell that thing was normal. And he would have been willing to chalk it up to lack of oxygen, were it not for the single scale caught in his swimsuit, muddy brown and dagger-sharp. Or, at least...muddy brown, until the late-afternoon sun hit it just so, setting it afire in marbled tones of iridescent green and sparkling beige.

Martin’s pretty sure  _ that _ isn’t normal.

* * *

Martin arrives at the river the next day armed with three disposable cameras. He’ll be damned if he isn’t at least  _ marginally _ prepared to look for and/or document any strange occurrences that may happen. Where there’s smoke, there’s fire, he guesses. Where there’s...giant fish monsters, there’s...other supernatural things?

No, Martin decides, the metaphor does not work. Or is it an allusion?

Martin is staring off into space, having achieved some sort of transcendent mental blankness, when Timothy Stoker rolls up in a baby-blue VW Camper. 

Wow. That’s definitely a choice, Martin supposes. It looks like someone painted a brick and set it on wheels. Least there’s plenty of storage, though; he can see two kayaks lashed to the clunky van’s rack. Tim’s arm is perched on the open window, leaning out to shout to Martin from across the parking lot. The driver’s side door opens, and out steps a lanky woman, a broad smile splitting her face as she shields her eyes from the noonday sun.

Martin’s jaw drops. He tries to walk over to them casually, but he doesn’t think he’s quite concealing the excited bounce in his step.

“Tim,” he says, definitely not gawking at the woman next to him. “You, ah--you didn’t mention that your friend Sasha was  _ Sasha James _ .”

“In the flesh,” Sasha says, laughing. “It’s so nice to meet you, Martin. Heard a lot about you from Tim, here.”

Martin cocks an eyebrow. “Oh yeah?”

Tim chuckles, raising a self-conscious arm behind his head. “A little bit. Figured you and Sash would get on pretty well.”

Martin shakes his head in disbelief. “It’s--it’s honestly an honor to meet you, Sasha.”

“Oh, please don’t act like I’m a big deal or anything!” She really does have a nice laugh, airy and cheerful. It reminds Martin of...a bird, maybe. Something small and bouncy. It’s almost hard to believe that this is the same person that smashed the North Fork Championship record. Hell, he’s seen the video of her doing laps on Great Falls, all the way in America. For  _ fun _ . Martin wishes he had half of her guts, let alone her talent.

“You are, though!” Martin beams.

Tim rolls his eyes exaggeratedly. “See, that’s what I mean. Twin balls of sunshine.” Sasha elbows him in the side.

“Betrayed! Betrayed by my best friend!” Tim cries, folding over in mock pain. “How could you?”

“Oh, get over it, Stoker,” Sasha says, smiling wide.

“Eeeauuurgh,” he moans, now lying prone on the gravel. They have an easy charm to them, these two, Martin learns. Enough to keep all three of them  _ very _ amused the entire way to the river. Tim cracks jokes that are so awful, even though it’s not exactly a fun hike, carrying all their gear, that by the time they reach the put-in, Martin’s stomach aches from laughter. Tim and Sasha, thankfully, have been generous enough to loan him some stuff, hopefully just until he can replace what he lost. 

They spend some time practicing ferries, taking turns crossing the rapid. Tim is training for his swiftwater rescue certification test, so Sasha and Martin have fun pretending to not be able to swim. They have a particularly close call when Tim flubs a carry and ends up bonking Martin in the head with his paddle. He’s too busy apologizing to Martin to notice how far downriver they’re floating, but some quick thinking by Sasha and a throw rope fixes the problem in no time.

And Martin is...genuinely happy, for some reason. 

Before long, the sun is starting to set, and he realizes that, for the first time in a while, he doesn’t want this day to end. The almost-drowning might just be the best thing that’s happened to him in a while. Which is really sad, but also weirdly okay with him.

As the sun begins to dip towards the horizon, the shadows lengthening, Martin relaxes on the bank, back propped against a warm rock. He watches Sasha dunk Tim, both of them disappearing around the bend. Martin feels his eyes begin to close, as he lets out a deep sigh. Damn, he’s tired. Surely no one would mind if he just dozed off a little.

He hears a thunk above his head and he blinks awake, startled. “Tim--uh, sorry, I was just--” he yawns, pushing himself to his feet. He looks around, a bit sheepish, preparing to apologize. He didn’t really mean to fall asleep. He knows how rude that would be, how inconsiderate it would look--but as he turns around in a full circle, there’s nobody there.

“Hello?” he asks, puzzled. He’s about to sit back down when his eyes land on a paddle, carefully balanced atop the rock he was leaning against.  _ His _ paddle.

_ What? _ Martin stares at it in absolute bewilderment. No, that’s definitely his--same pink-and-white blade, same chipped t-grip, same circle of electrical tape around the shaft. He picks it up with both hands, turning it over in his fingers, before he comes back to himself. Unless the river had suddenly just gained sentience,  _ someone _ had put it there. It wasn’t Sasha or Tim; they were nowhere to be seen. Could it have been another kayaker or paddleboarder, the paddle having been found washed up in some eddy? Sure, maybe--but then where was that person now? Wouldn’t they have stayed around to make sure it was his? And, to that point, how would they know it was his paddle?

Martin fumbles around himself for any of the cameras. He doesn’t know how they’ll help, but they might do something. He finds a single one, tucked away in a pocket on his lifejacket. He holds it up in front of himself like a ward. A bright yellow plastic ward.

His mother’s voice rises unbidden to the forefront of his mind. G-d, what was he thinking? He was going to document some sort of paranormal entity? His hands begin to shake.  _ Idiot. _

The cameras go into the river. Littering, yes, but Martin is past caring. He tells himself that, anyways, and tries not to feel guilty. Instead, he scratches three words into the top of the rock, directly underneath where he had found his paddle.

_ Who are you? _

As an afterthought, he adds a little heart next to the question mark. It just makes the message feel a little bit friendlier. Speaking of friendly, too, Tim and Sasha come back, each hoisting a kayak over their shoulder.

“Sorry about that, Martin,” Tim says, slightly out of breath. “We got swept away a little bit.”

Martin shrugs, shoulders rising and falling like a wave. “Oh, uh--no--no worries.” He holds up his paddle. “Check it out.”

Sasha’s eyes widen. “Is that the paddle you lost?”

Martin nods enthusiastically. “Yeah!”

“No way, man,” Tim says, clapping him on the shoulder. “Insane. Where’d you find it?”

“I, uh--” He hesitates for the briefest of seconds. “Found it washed out up there.”

Why is he lying to them? He feels the message in the rock burn into his back, each letter a searing brand on his skin. They’re not able to see it, he doesn’t think. Too small, and too far away. 

“That’s great news,” Sasha says. “Hey, me and Tim were thinking we’d do one last run and head home. That alright with you?”

“Yeah, ah--totally,” Martin says. “Actually, you know what? I might--I might try and stay, er, a bit longer. Feeling--sorta out of practice.”

Tim bobs his head. “For what it’s worth, you’re looking great out there. But, totally cool. Always room for a little extra work, like Sash says.”

“You’re a jerk,” Sasha says, affection coloring her voice. “But, yeah. Have fun, Martin! We’ll keep in touch.” They wave goodbye and depart, leaving Martin once again alone.

He stares pointedly at the rock, on which no further messages have magically manifested. He’ll leave it alone for a bit, he decides. Watched pot never boils, and all that. He puts his helmet back on and prepares to take his board out for another go. As he paddles out from the eddy, he hears a splash. Immediately, he whips around, looking intently at the river. 

Nothing. Maybe this area really just has extremely large fish?

Then he notices the rock. Carved into it, with jagged slashes, is the word “Nobody.”


End file.
